Portable adjustable back lift system

ABSTRACT

A portable lightweight back lift system is made from a back support upper frame portion and a lower base frame portion. Both frames are hinged together at one end enabling the angle between them to be changed. A support frame is hinged to the side members of the upper frame and slides over the side members of the lower base frame. The upper frame is held in place by securing pins, which lock the angle of inclination of the back support upper frame portion according to the needs of a user. The bottom surface of the lower base frame portion is covered by a high friction material, so that the back lift system does not slide over a flat bed surface when a user leans against the back lift system. Each of the frames is composed of welded or glued lightweight tubular material, such as aluminum or polymeric material.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to back lift systems; and, moreparticularly, to a light weight back lift system appointed for use incombination with a conventional bed to orient and change the angle ofinclination of the back rest to facilitate viewing of television,reading and other activities.

2. Description of the Prior Art

Many patents address issues related to back lift systems. These patentsdisclose cumbersome bed lift devices that are laden with complicatedmachinery; or are not portable due their weight; or are attachedpermanently to the bed.

U.S. Pat. No. 1,336,294 to Hackman discloses a bed rest. The bed resthas a crank (19) that turns a rod element (17) with right handed threadsat one end and left handed threads at the other end, engaging with twolugs (14) having corresponding threads displacing the lugs in oppositedirections. The lugs are connected to rod elements (12 and 13), whichhave rod end sleeves (10) that slide and displace laterally toaccommodate the displacement of lugs (14). When the body weight of auser on the top portion is applied, the sleeves (at 10) may slide sincelugs (at 14) do not restrain a downward movement of the top portion (5).As a result, the bed rest does not provide reliable back support.

U.S. Pat. No. 3,931,653 to Bien discloses a power operated backrest.This body rest apparatus has a base adapted to be placed on a supportsurface. This backrest is actuable to different inclined positionsrelative to the base by a motor driven screw and nut mechanism locatedwithin the dihedral angle formed between the base and backrest elements.The motor turns a screw element, which pushes a swing plate against theback plate to change its angular position. The backrest (17) restsagainst the edge of the swing plate (30). Accordingly, there is nophysical restraint for the backrest, which may freely swing, losingcontact with the edge of the swing plate.

U.S. Pat. No. 4,185,342 to Young discloses a portable, adjustablebackrest for beds and the like. This portable, adjustable backrest isdesigned for use primarily on a bed, sofa or the like and takes the formof a backrest panel connected by a hinge to a base which is placed uponthe bed, sofa or the like. The backrest panel is designed to beadjustable with respect to the base in various inclined positions. Theadjustments of the backrest panel are provided through a crank armassembly, which operates through a disc assembly. This disc assembly, inturn, rolls upon a thin flexible strap assembly. An arm assembly isattached to the disc assembly, which is adapted to pivot with the discassembly. The outer end of the arm assembly is designed to be in contactwith the backside of the backrest panel. The pivoting of the armassembly to different positions results in locating of the backrestpanel to various inclined positions with respect to the base. Thisbackrest is not indicated to be a lightweight portable device and is notplacable in the middle of a bed due to the protrusion of the hand crank.

U.S. Pat. No. 4,458,370 to Fickler discloses a device for adjusting theangular position of a movable supporting surface. This device isdesigned for adjusting the angular position of a movable support. It hastwo frames, which are pivotally connected to each other along a pivotaxis and are capable of being moved apart by the action of pre-tensionedtorsion spring rods provided near the pivot axis so that the two framesassume variable angular positions with respect to each other. Themovable support frame in its upwardly directed angular position mayserve as a supporting surface for a mattress at the head end of a bedframe. To effect angular adjustment, two steel cables fastened to oneframe are trained over pulleys disposed on the other frame and areguided to a pivot lever pivotably attached to the other frame and areactuated by an electric motor. As the motor is operative, the steelcables cause the frames to be pulled in one direction toward each otheragainst the action of the torsion spring rods and the pneumatic springs.Reversing the direction of the motor will cause the frames to move awayfrom each other due to the action of the torsion spring rods andpneumatic springs. This device is a complicated lifting mechanism with amotor, steel cables, pulleys, and pneumatic springs. The presence ofsprings allows movement of the backrest according to the spring constantprovided and is therefore not a backrest that provides steady support tothe back. The steel cable and pivotal arrangements provided also resultin slack within the backrest support.

U.S. Pat. No. 4,754,507 to Edge discloses a back rest device. This backrest device comprises frame means, a back rest, and connecting means forpivotally connecting the back rest to the frame means such that the backrest is pivoted during use and can be changed from a substantiallyvertical position and an inclined position. The connecting means enableup and/or down movement of the back rest as it is pivoting between thesubstantially vertical position and the inclined position whereby theback rest is able to rise over any obstacles that may be in the way.This back rest is permanently attached by bolts to the divan (which isbelow the mattress of a bed). The device disclosed by the '507 patent isnot portable. When not in use, the back rest folds to a verticalposition. In use, the back rest is inclined. Consequently, it slides onthe mattress surface creating a “digging” action, which tends to damagethe mattress surface.

U.S. Pat. No. 4,853,990 to Elder et al. discloses a mechanical backlift.This is a person-raising device, designed for lifting a person in bed.The device rests atop a bed and is activated by a linear actuator. Theactuator comprises a dual-threaded lead screw and a small electric motorand gear reduction unit. The small electric motor and gear reductionunit drives the dual-threaded lead screw to raise a pair of supportarms, which raises a person resting on the device. The lead screw isenclosed in a slotted tube; this decreases the chance of the lead screwcoming into contact with a person using the device. The mechanical backlift disclosed by the '990 patent is a heavy motorized device. A motor,gearbox and lead screw are contained within a tube that forms the baseof the device. Such an apparatus is not a lightweight portable device.

U.S. Pat. No. 5,425,150 to Palmer, Jr. et al. discloses an articulatingdevice for a flat bed. This device converts a flat bed into anadjustable bed. The system (10) has a base (20) which mounts on thebed's box-springs (14) and an articulating platform (30) sandwichedbetween the box-springs (14) and the mattress head section (18A). Thearticulating platform (30) pivots about the pivoting end (28) of base(20) by inflating bellows (40). The controls (42, 43, 44) provide foradjustable firmness, degree and speed of pivoting, and delay for thestart of the deflating of bellows (40) for lowering articulatingplatform (30). This device has the base permanently attached to themattress box spring. Consequently, the device is not portable. Airbellows are pressurized to incline the device, which does not rest onthe surface of the bed.

U.S. Pat. No. 5,829,077 to Neige discloses a device for tilting the topend and/or bottom end of a bed. This device is designed for tilting thetop end and/or bottom end of a bed. Two frames are connected by a hinge.A control unit connected to the hinge adjusts the spacing between thetwo frames. One fixed frame is supported on the bed base while the othermovable frame supports one end of a mattress. The fixed frame comprisestwo parallel co-planar tubes and the movable frame consists of aU-shaped frame pivotably mounted on and between the tubes. The controlunit is attached to the fixed frame and controls the longitudinaltranslation of slide blocks with worm screws. The blocks are slidablealong the tubes to tilt the movable frame relative to the fixed frame.The worm screws are mounted in the two tubes and the control unit islocated outside the area encompassed by the fixed frame. This is amotorized device attached to a bed for tilting the head and the foot ofa bed. This complicated device is heavy. It is not portable and operatesto incline only the head portion of a patient resting on a bed surface.

U.S. Pat. No. 5,926,876 to Haigh et al. discloses a surgical operatingtable accessory for shoulder procedures. This device is designed foradapting a surgical operating table such that the upper torso of thepatient can be raised in order to place the patient in a seatedposition. The device further provides the means of exposing orsupporting a side of said patient's upper torso and limbs. The devicecontains a continuously adjustable positioning mechanism, andcorresponding actuator for said mechanism, in a way that a user canrapidly and conveniently put a patient in the desired position, from asupine posture to a fully seated position. Additionally, the device doesnot render the surgical table permanently modified, as the process ofmodification is reversible by means of a simple attachment mechanism.The device uses a back support section hingedly connected to a baseframe, which provides the attachment support to the surgical table. Sidesupport panels are either moved out of the way on the patient'soperative side, or left in place to provide support to the unaffectedside. Two embodiments are described that differ solely in the way theback support surface is implemented. The surgical operating tableaccessory disclosed by the '876 patent is attached to an operatingtable. It is a heavy bulky device that is not portable. U.S. Pat. No.5,937,459 to Binaghi et al. discloses a pillow lifting device,particularly suited for beds and the like. A first fixed structure isarranged at the region where the user's head is meant to rest. A secondstructure is pivoted to the first fixed structure at one end and issuitable to support a pillow. The elements for lifting/lowering thesecond structure with respect to the first fixed structure comprise anelongated element actuated by a motor. The pillow lifting mechanismdisclosed by the '459 patent is a motorized, heavy device. It ispermanently attached to a bed, and is not portable.

U.S. Pat. No. 7,240,385 to Brown discloses a device designed for raisingat least a portion of a mattress. This device is positioned between abox spring and a mattress and selectively raises a portion of themattress. The device has a base frame secured to the box spring or boxspring frame. A mattress supporting frame is pivotally coupled to thebase frame. A leveraging arm with a roller bearing is pivotally coupledto the base frame. A linear actuator having an electric motor and adisplaceable shaft is pivotally coupled to the leveraging arm. Extensionof the shaft pivots the leveraging arm upwardly, raising the rollerbearing against a cross member of the mattress supporting frame to lifta portion of the mattress. Mattress restraining members prevent themattress from shifting as the mattress is raised. The base frame isadapted to nest within the mattress supporting frame when the device isin a lowered position to minimize the vertical space required for thedevice. The device disclosed by the '385 patent is permanently attachedto a bed frame, and therefore is not a portable backlift.

Foreign Patent Application No. DE 3119524 to Braun discloses portableappliance for lifting and lowering loads, in particular beds or bedbases. It has a lifting device, which can be attached, for example, tothe underside of a bed. This lifting device is equipped with a liftingplatform adjustable rectilinearly in the vertical direction andreceiving the load. The appliance can be set up under the bed to liftbedridden patients to a favorable height for making the bed. It ispossible to merely lift the bed frame covered with a mattress out of thebed frame and lower it again into the bed frame. This is said to beuseful in the case where double beds are assembled and, consequently, abed as such cannot be lifted. The portable appliance for lifting andlowering beds, as disclosed by the '524 patent is attached to the bed tolift the mattress with the patient; and therefore is not a portabledevice.

There remains a need in the art for a lightweight back rest whichenables the angle of support for the back of a person to be reliablyadjusted in a stable manner. When the back rest orientation may need tobe varied by the person using the bed to better view TV or the like,this change in the orientation of the back rest should be accomplishedeasily. The back rest should not slide on the bed surface under theweight of the inclined person resting thereon.

SUMMARY OF THE INVENTION

The present invention provides a lightweight portable back lift system,which can be used when lying on a flat bed to lift the back at anyconvenient angle. Since the bottom surface of the back lift system has ahigh friction surface, the weight of the user loads the friction bottomsurface of the back lift system against the top surface of the bed.Consequently, the bed rest remains fixed on the bed at any selectedlocation when the user rests thereon. When the user releases the weightloading, the back rest may be moved easily on the bed surface to a newlocation. This allows the user to easily change the viewing angle tobest observe a television program, or the like. The user may be ahousehold resident or a patient in a hospital bed.

Briefly stated, the invention of the back lift comprises an upperadjustable rectangular portion that supports the torso above the waistand the head of a user. The upper adjustable rectangular portion ishinged to a rectangular lower fixed rectangular base portion that isprovided with a high friction bottom surface, which rests on a flat bed.The angle of inclination of the upper rectangular portion can be readilychanged and locked in place by displacing a supporting frame thatbridges between the upper rectangular portion and the lower rectangularbase portion. The supporting frame may constructed with one or morelinked support structures. In one embodiment, the supporting frame is ahinged rectangular frame which is pivoted by a hinge at the side membersof the upper rectangular portion and which contacts the lower baseportion, providing support. The user lies on the flat surface of the bedwith the waist nearly in line with the hinge between the upperrectangular portion and the lower rectangular portion. The angle betweenthe torso supporting rectangular portion and the lower rectangular baseportion may be selected at any angle ranging from zero, a flat position,to a maximum inclination angle of typically 85 degrees. The angle ofinclination of the upper rectangular portion is changed by theattachment location of the link member and the fixed rectangular baseportion. The attachment location may include a plurality of apertures inthe lower rectangular base and the link member. A pin is insertedthrough the aligned apertures connecting the upper rectangular portionsecurely at the user selected angular inclination.

The upper rectangular portion and lower rectangular base portion areframes made from light weight, low density material such as aluminumtubing or polymeric tubing welded or bonded by appropriate glue. A hingeholds the two frames together and the angle between the frames can bechanged easily. When this angle is brought to zero, the upperrectangular frame lies over the lower rectangular base portion, so thatthe back lift is compact and can be readily transported.

Significant advantages are realized by practice of the presentinvention. The key elements of the portable adjustable back lift systemof the present invention comprise:

1) A lightweight foldable adjustable system composed of lightweight,glued polymeric tubes or welded aluminum tubes;

2) the tubes forming a base rectangular frame with two edge members andtwo side members;

3) the tubes forming an adjustable back support rectangular frame withtwo length members and two side members;

4) the base rectangular frame and adjustable back support frame beinghinged at one end so that the angle between the two rectangular framesis changeable;

5) the adjustable back support frame having a central rod connecting itsside members and carrying one end of a hinged supportive rectangularframe;

6) the other end of said supportive rectangular frame having channeledlegs that slide over side members of said base frame, and are lockableat a plurality of positions to fix the angle between the baserectangular frame and the adjustable back support rectangular frame;

7) the bottom surface of said base rectangular frame being provided witha high friction surface;

whereby the adjustable back support is adjusted and locked in desiredangular position and placed on a bed surface, and is prevented fromsliding by the high friction surface on the bottom surface of the baserectangular frame in combination with the weight of the user.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be more fully understood and further advantages willbecome apparent when reference is had to the following detaileddescription of the preferred embodiments of the invention and theaccompanying drawing, in which:

FIG. 1 schematically illustrates the portable adjustable back liftsystem;

FIG. 2 schematically illustrates an alternate embodiment of lockingmechanism of the portable adjustable back lift system;

FIG. 3 illustrates the details of the latching mechanism that locks thesupporting frame against the lower base frame.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to a lightweight, portable adjustable back liftsystem. The user is easily able to carry the portable back liftanywhere. The folded device is placed on a bed with the base rectangularframe friction surface resting on the bed surface. The user then opensout the adjustable rectangular frame and inclines it to a desirableangle. In addition, the user can pull out the folded support rectangularframe that is hinged to the central rod of the adjustable frame andlocate and lock the legs of the support rectangular frame on the baserectangular frame side members. The user's back may now be brought torest against the adjustable frame. The weight of the user, incombination with the friction surface underneath the base rectangularframe, prevents sliding of the portable adjustable back lift system onthe bed surface.

Briefly stated, the invention involves a back lift comprising an upperadjustable rectangular portion that supports the torso above the waistand the head of a user. A rectangular lower fixed rectangular baseportion of the back lift rests on a flat bed. The torso supportingportion and the base rectangular portion are hinged to each other at oneend so that the angle between the torso supporting rectangular portionand the base portion may be selected. Angles available for selectionrange from zero, a flat position, to a maximum inclination angle. Theangle is changed by one or more hinged link members. The attachmentlocation of connections between link members and the fixed rectangularbase portion may be continuously varied by selecting a desired angularlocation of the upper adjustable rectangular supporting portion withrespect to the fixed base portion. Such a selection is readily effectedby manual means or an electrical motor drive.

Particularly, the portable adjustable back lift system comprises a baserectangular frame portion having its bottom surface coated with highfriction material. An adjustable rectangular frame portion is hinged tothe base rectangular frame. The adjustable rectangular frame has acentral rod that includes a hinged connection to a distal end of asupport rectangular frame. With this arrangement, the supportrectangular frame can be inclined at virtually any angle with respect tothe adjustable rectangular frame. The proximal end of the supportrectangular frame has two channeled legs that ride on the side membersof the base rectangular frame. This construction enables the angle ofthe adjustable rectangular frame to be adjusted with respect to the baserectangular frame, as the channeled legs are slid along the side membersof the base rectangular frame. The legs of the support frame havelocking features. Accordingly, the location of the support frame on thebase rectangular frame may be locked so that the angle of the adjustableframe with respect to the base rectangular frame remains fixed.

The user places the portable adjustable back lift on the bed surface sothat the base rectangular frame with the bottom friction surfacecontacts the bed surface. The user then raises the adjustablerectangular frame from the zero position to the desired angle. Thesupport rectangular frame that is hinged to the central rod of theadjustable frame at one end is adjusted so that the two legs of thesupport rectangular frame ride on the side members of the baserectangular frame. The angular location of the adjustable frame is fixedwhen the user locks the channels provided on the legs; these channelsare locked against the side members of the base rectangular frame. Thelocking means may be a plurality of holes through which a pin isinserted; such insertion is effected through the leg member and the sidemember of the base rectangular frame.

FIG. 1 illustrates generally at 10 a schematic sketch of the back liftsystem. The back lift comprises upper adjustable portion 12 and baseportion 11, both being generally rectangular and sized such that upperportion 12 accommodates generally the torso and head of the subject. Thebase rectangular portion has two side members with a plurality ofapertures 13 for locking the upper adjustable portion 12 at a specificangular position φ using a support frame. Portions 12 and 14 areconnected at their bottom edges by a hinge 16. Bottom portion 11 isappointed to rest on a conventional bed (not shown) and has a highfriction under surface so the device does not slide on the bed when aperson's torso is rested on the back lift. The high friction coating onthe bottom of base portion is shown at 11A. In typical use, a subjectlies on the bed with his/her waist approximately aligned with hinge 16.By elevating upper portion 12, the head and torso bend generally at thewaist, and are supported by portion 12.

The details of the manufacture and operation of the portable adjustableback lift are shown in FIG. 1. The base portion 11 that rests on the bedis made as a rectangular frame by gluing or welding light weightpolymeric tubes or aluminum tubes with the bottom bed contacting surfacecovered with a high friction material such as sand paper, terry clothand the like. Similarly, the adjustable frame 12 is also made fromlightweight polymeric tubes or aluminum tubes joined together by gluingor welding to form a rectangular frame. One end of the adjustable frameis hinged at one end of the base frame to form a hinge 16. The hingearrangement is such that the angle between the base frame and theadjustable frame may be readily changed. The adjustable frame hascentral rod 14 that carries a support rectangular frame 15 hinged at 17.This hinge connection may be of any construction type including a largetube that captures both the adjustable frame distal edge and the distalend of the rectangular support frame. In this manner, the supportrectangular frame may be inclined at any angle with respect to theadjustable frame. The proximal end of the support rectangle carries twochanneled legs 18 with a locking aperture that ride on the two lateraltubes of the base rectangle. Thus, as the support rectangle channeledlegs slide along the side lateral tubes of the base rectangular frame,the angle φ between the base rectangle and the adjustable frame ischanged. This movement of the legs of the support rectangle may bemanual or motor assisted. A secure locking arrangement is provided onthe channeled legs to lock the support frame at a chosen position on thebase rectangular frame using bolts 19 inserted through the apertures ofthe channel guide 18 and apertures of the side elements of the baseframe at 13. Thus, when the back lift is assembled at a particularangle, and the person's torso is placed against the adjustable frame, alarge weight is applied to the device and the friction surface under thebase plate prevents sliding of the device. However, when the personremoves his or her weight from the adjustable, the location of theadjustable back lift on the bed surface may be easily changed, allowingthe user to orient the sitting posture to comfortably view TV or otheractivities, including reading.

FIG. 2 schematically illustrates at 20 an alternate embodiment for thelocking mechanism of the portable adjustable back lift system. Thisembodiment uses a pin 21 that integrally attached within the side memberof the support frame 15 and can be inserted within the matchingapertures of the channel 18 and aperture 13, which are provided in theside members of the lower base frame 11.

FIG. 3 illustrates at 30 the details of the latching mechanism thatlocks the supporting frame against the lower base frame. The pin 21 hasa head 31 that prevents escape of the pin 21 from the side member 15 ofthe supporting frame. The figure A shows the condition when the pin maybe pulled out from the apertures, and the supporting frame displaced toselect a different inclination angle for the back support upper frame.As shown in figure B, the pin 21 is slid back into matching apertures inthe channel 18 and aperture 13 of the lower base frame side memberfixing the angle of inclination selected by the user. In this manner,the pin is not lost and is always available.

Having thus described the invention in rather full detail, it will beunderstood that such detail need not be strictly adhered to, but thatadditional changes and modifications may suggest themselves to oneskilled in the art, all falling within the scope of the invention asdefined by the subjoined claims.

1. A portable lightweight back lift system, comprising: a) a backsupport upper frame portion and a lower base frame portion; b) each ofsaid upper frame portion and lower base frame portion having two sidemembers, and each of said back support upper frame portion and lowerbase frame portion having two edge members; c) said lower base frameportion having a high friction bottom surface; d) said upper frameportion and lower base frame being hinged at one end so that the angletherebetween can be changed; e) said upper frame portion having a hingedsupport frame; f) said hinged support frame contacting said lower baseframe portion and secured thereto; and g) said side members of saidlower base frame portion having a plurality of locking apertures;whereby the back support upper frame portion is secured at a userselected angle with respect to the lower base frame portion, and saidportable lightweight back lift system can be placed on a flat bedsurface to support the user at a selected location on the bed surface byinclining and supporting the back of the user at the selectedinclination angle.
 2. (canceled)
 3. (canceled)
 4. The portablelightweight back lift system as recited by claim 1, wherein said thehinged support frame has two channels with apertures that contact andrest against the side members of the lower base frame portion and arelocked by a set of securing pins.
 5. The portable lightweight back liftsystem as recited by claim 4, wherein said securing pin is secured tothe side members of the support frame, preventing its misplacement. 6.The portable lightweight back lift system as recited by claim 1, whereinsaid angle of inclination of the back support upper frame portion withrespect to the lower base frame portion ranges from 0 to 85 degrees. 7.A method of using a portable lightweight back lift system, comprisingthe steps of: a) inclining the back support upper frame portion withrespect to the lower base frame portion at the hinge to a desired angle;b) extending the support frame at the hinge of the side members of theupper frame portion and contacting the end distal from the hinged endagainst side members of the lower base frame portion to secure acontacting location; c) orienting the back lift system on a flat bedsurface at a location convenient for viewing television or otheractivities; whereby the weight of the user on the back support upperframe portion applies load to the high friction undersurface of thelower base frame portion, preventing sliding of the back support systemon the flat bed surface during use.